In recent years, in the fields of medicine, biochemistry, molecular biology, and the like, it has become important to detect biomolecules such as proteins, various antigen molecules, DNA (deoxyribonucleic acid), and RNA (ribo nucleic acid). In particular, the amount of samples of those biomolecules is very small, from pmol to fmol order, depending on cases, so a development of a highly sensitive and highly accurate detection method is demanded.
As a highly sensitive detection method, a method of detecting fluorescence is most typically used. In the detection method of the fluorescence, for example, a target material to be detected is labeled in advance with a fluorescent marker, and an optical sensor to which a probe material that mutually acts with the target material specifically is fixed is used to detect the fluorescence from the target material that is adsorbed to the probe material.
For example, Patent Document 1 discloses an organic molecule detection semiconductor element in which a silicon substrate on which an organic molecule probe disposition area is formed and a solid state image pickup element are integrated with each other. The element has the structure in which fluorescence generated by bonding a target material with an organic molecule probe disposed in the organic molecule probe disposition area is detected by the solid state image pickup element.
Further, Patent Document 2 discloses a biopolymer analysis chip in which an on-chip lens is provided between spots formed of a double gate transistor (photoelectric conversion element) and a probe material. On the chip, fluorescence generated from the target material that is bonded with the probe material is collected by the on-chip lens and is detected by the double gate transistor.    Patent Document 1: Japanese Patent Application Laid-open No. 2002-202303    Patent Document 2: Japanese Patent Application Laid-open No. 2006-4991